status: never assume empty blobs are unencrypted

See comment in source code for rationale.

README

@@ -30,6 +30,7 @@ Specify files to encrypt by creating a .gitattributes file:
 
 	secretfile filter=git-crypt diff=git-crypt
 	*.key filter=git-crypt diff=git-crypt
+	secretdir/** filter=git-crypt diff=git-crypt
 
 Like a .gitignore file, it can match wildcards and should be checked into
 the repository.  See below for more information about .gitattributes.
@@ -54,7 +55,7 @@ are added to your repository):
 
 	$ git-crypt export-key /path/to/key
 
-After cloning a repository with encrypted files, unlock with with GPG:
+After cloning a repository with encrypted files, unlock with GPG:
 
 	$ git-crypt unlock
 
@@ -108,6 +109,16 @@ git-crypt does not hide when a file does or doesn't change, the length
 of a file, or the fact that two files are identical (see "Security"
 section above).
 
+git-crypt does not support revoking access to an encrypted repository
+which was previously granted. This applies to both multi-user GPG
+mode (there's no del-gpg-user command to complement add-gpg-user)
+and also symmetric key mode (there's no support for rotating the key).
+This is because it is an inherently complex problem in the context
+of historical data. For example, even if a key was rotated at one
+point in history, a user having the previous key can still access
+previous repository history. This problem is discussed in more detail in
+<https://github.com/AGWA/git-crypt/issues/47>.
+
 Files encrypted with git-crypt are not compressible.  Even the smallest
 change to an encrypted file requires git to store the entire changed file,
 instead of just a delta.
@@ -138,15 +149,16 @@ specifying merely a directory (e.g. `/dir/`) is NOT sufficient to
 encrypt all files beneath it.
 
 Also note that the pattern `dir/*` does not match files under
-sub-directories of dir/.  To encrypt an entire sub-tree dir/, place the
-following in dir/.gitattributes:
+sub-directories of dir/.  To encrypt an entire sub-tree dir/, use `dir/**`:
+
+	dir/** filter=git-crypt diff=git-crypt
+
+The .gitattributes file must not be encrypted, so make sure wildcards don't
+match it accidentally.  If necessary, you can exclude .gitattributes from
+encryption like this:
 
-	* filter=git-crypt diff=git-crypt
 	.gitattributes !filter !diff
 
-The second pattern is essential for ensuring that .gitattributes itself
-is not encrypted.
-
 
 MAILING LISTS
 

README.md

@@ -31,6 +31,7 @@ Specify files to encrypt by creating a .gitattributes file:
 
     secretfile filter=git-crypt diff=git-crypt
     *.key filter=git-crypt diff=git-crypt
+    secretdir/** filter=git-crypt diff=git-crypt
 
 Like a .gitignore file, it can match wildcards and should be checked into
 the repository.  See below for more information about .gitattributes.
@@ -55,7 +56,7 @@ are added to your repository):
 
     git-crypt export-key /path/to/key
 
-After cloning a repository with encrypted files, unlock with with GPG:
+After cloning a repository with encrypted files, unlock with GPG:
 
     git-crypt unlock
 
@@ -110,6 +111,16 @@ git-crypt does not hide when a file does or doesn't change, the length
 of a file, or the fact that two files are identical (see "Security"
 section above).
 
+git-crypt does not support revoking access to an encrypted repository
+which was previously granted. This applies to both multi-user GPG
+mode (there's no del-gpg-user command to complement add-gpg-user)
+and also symmetric key mode (there's no support for rotating the key).
+This is because it is an inherently complex problem in the context
+of historical data. For example, even if a key was rotated at one
+point in history, a user having the previous key can still access
+previous repository history. This problem is discussed in more detail in
+<https://github.com/AGWA/git-crypt/issues/47>.
+
 Files encrypted with git-crypt are not compressible.  Even the smallest
 change to an encrypted file requires git to store the entire changed file,
 instead of just a delta.
@@ -140,15 +151,16 @@ specifying merely a directory (e.g. `/dir/`) is *not* sufficient to
 encrypt all files beneath it.
 
 Also note that the pattern `dir/*` does not match files under
-sub-directories of dir/.  To encrypt an entire sub-tree dir/, place the
-following in dir/.gitattributes:
+sub-directories of dir/.  To encrypt an entire sub-tree dir/, use `dir/**`:
+
+    dir/** filter=git-crypt diff=git-crypt
+
+The .gitattributes file must not be encrypted, so make sure wildcards don't
+match it accidentally.  If necessary, you can exclude .gitattributes from
+encryption like this:
 
-    * filter=git-crypt diff=git-crypt
     .gitattributes !filter !diff
 
-The second pattern is essential for ensuring that .gitattributes itself
-is not encrypted.
-
 Mailing Lists
 -------------
 

commands.cpp

@@ -51,6 +51,12 @@
 #include <exception>
 #include <vector>
 
+enum {
+	// # of arguments per git checkout call; must be large enough to be efficient but small
+	// enough to avoid operating system limits on argument length
+	GIT_CHECKOUT_BATCH_SIZE = 100
+};
+
 static std::string attribute_name (const char* key_name)
 {
 	if (key_name) {
@@ -183,15 +189,19 @@ static void deconfigure_git_filters (const char* key_name)
 	}
 }
 
-static bool git_checkout (const std::vector<std::string>& paths)
+static bool git_checkout_batch (std::vector<std::string>::const_iterator paths_begin, std::vector<std::string>::const_iterator paths_end)
 {
+	if (paths_begin == paths_end) {
+		return true;
+	}
+
 	std::vector<std::string>	command;
 
 	command.push_back("git");
 	command.push_back("checkout");
 	command.push_back("--");
 
-	for (std::vector<std::string>::const_iterator path(paths.begin()); path != paths.end(); ++path) {
+	for (auto path(paths_begin); path != paths_end; ++path) {
 		command.push_back(*path);
 	}
 
@@ -202,6 +212,18 @@ static bool git_checkout (const std::vector<std::string>& paths)
 	return true;
 }
 
+static bool git_checkout (const std::vector<std::string>& paths)
+{
+	auto paths_begin(paths.begin());
+	while (paths.end() - paths_begin >= GIT_CHECKOUT_BATCH_SIZE) {
+		if (!git_checkout_batch(paths_begin, paths_begin + GIT_CHECKOUT_BATCH_SIZE)) {
+			return false;
+		}
+		paths_begin += GIT_CHECKOUT_BATCH_SIZE;
+	}
+	return git_checkout_batch(paths_begin, paths.end());
+}
+
 static bool same_key_name (const char* a, const char* b)
 {
 	return (!a && !b) || (a && b && std::strcmp(a, b) == 0);
@@ -439,6 +461,25 @@ static std::pair<std::string, std::string> get_file_attributes (const std::strin
 	return std::make_pair(filter_attr, diff_attr);
 }
 
+static bool check_if_blob_is_empty (const std::string& object_id)
+{
+	// git cat-file blob object_id
+
+	std::vector<std::string>	command;
+	command.push_back("git");
+	command.push_back("cat-file");
+	command.push_back("blob");
+	command.push_back(object_id);
+
+	// TODO: do this more efficiently - don't read entire command output into buffer, only read what we need
+	std::stringstream		output;
+	if (!successful_exit(exec_command(command, output))) {
+		throw Error("'git cat-file' failed - is this a Git repository?");
+	}
+
+	return output.get() == std::stringstream::traits_type::eof();
+}
+
 static bool check_if_blob_is_encrypted (const std::string& object_id)
 {
 	// git cat-file blob object_id
@@ -748,6 +789,10 @@ int clean (int argc, const char** argv)
 		return 1;
 	}
 
+	if (file_size == 0 && key_file.get_skip_empty()) {
+		return 0;
+	}
+
 	// We use an HMAC of the file as the encryption nonce (IV) for CTR mode.
 	// By using a hash of the file we ensure that the encryption is
 	// deterministic so git doesn't think the file has changed when it really
@@ -865,6 +910,11 @@ int smudge (int argc, const char** argv)
 	// Read the header to get the nonce and make sure it's actually encrypted
 	unsigned char		header[10 + Aes_ctr_decryptor::NONCE_LEN];
 	std::cin.read(reinterpret_cast<char*>(header), sizeof(header));
+
+	if (std::cin.gcount() == 0 && key_file.get_skip_empty()) {
+		return 0;
+	}
+
 	if (std::cin.gcount() != sizeof(header) || std::memcmp(header, "\0GITCRYPT\0", 10) != 0) {
 		// File not encrypted - just copy it out to stdout
 		std::clog << "git-crypt: Warning: file not encrypted" << std::endl;
@@ -969,6 +1019,7 @@ int init (int argc, const char** argv)
 	std::clog << "Generating key..." << std::endl;
 	Key_file		key_file;
 	key_file.set_key_name(key_name);
+	key_file.set_skip_empty(true);
 	key_file.generate();
 
 	mkdir_parent(internal_key_path);
@@ -1171,7 +1222,7 @@ int lock (int argc, const char** argv)
 	}
 	if (!git_checkout(encrypted_files)) {
 		std::clog << "Error: 'git checkout' failed" << std::endl;
-		std::clog << "git-crypt has been locked but up but existing decrypted files have not been encrypted" << std::endl;
+		std::clog << "git-crypt has been locked up but existing decrypted files have not been encrypted" << std::endl;
 		return 1;
 	}
 
@@ -1403,6 +1454,7 @@ int keygen (int argc, const char** argv)
 
 	std::clog << "Generating key..." << std::endl;
 	Key_file		key_file;
+	key_file.set_skip_empty(true);
 	key_file.generate();
 
 	if (std::strcmp(key_file_name, "-") == 0) {
@@ -1607,7 +1659,8 @@ int status (int argc, const char** argv)
 
 		if (file_attrs.first == "git-crypt" || std::strncmp(file_attrs.first.c_str(), "git-crypt-", 10) == 0) {
 			// File is encrypted
-			const bool	blob_is_unencrypted = !object_id.empty() && !check_if_blob_is_encrypted(object_id);
+			// If the file is empty, don't consider it unencrypted, because in newly-initialized repos (specifically those with keys with skip_empty set) we don't encrypt empty files. Unfortunately, we can't easily determine here if the key has skip_empty set, so just act like it is. This means we won't notice if an old repo has an empty unencrypted file that should be encrypted. Fortunately, this isn't really a big deal because empty files obviously don't contain anything sensitive in them.
+			const bool	blob_is_unencrypted = !object_id.empty() && !check_if_blob_is_encrypted(object_id) && !check_if_blob_is_empty(object_id);
 
 			if (fix_problems && blob_is_unencrypted) {
 				if (access(filename.c_str(), F_OK) != 0) {

debian/changelog

@@ -1,19 +0,0 @@
-git-crypt (0.6.0-1) unstable; urgency=medium
-
-  * New upstream release.
-  * Build against OpenSSL 1.1.  (Closes: #851078)
-
- -- Andrew Ayer <agwa@andrewayer.name>  Sun, 26 Nov 2017 10:35:27 -0800
-
-git-crypt (0.5.0-2) unstable; urgency=medium
-
-  * Build against OpenSSL 1.0.x.  (Closes: #828312)
-  * Bump standards version (no changes needed).
-
- -- Andrew Ayer <agwa@andrewayer.name>  Wed, 23 Nov 2016 12:51:51 -0800
-
-git-crypt (0.5.0-1) unstable; urgency=medium
-
-  * Initial release. (Closes: #785346)
-
- -- Andrew Ayer <agwa@andrewayer.name>  Sat, 30 May 2015 20:22:22 -0700

debian/compat

@@ -1 +0,0 @@
-9

debian/control

@@ -1,24 +0,0 @@
-Source: git-crypt
-Maintainer: Andrew Ayer <agwa@andrewayer.name>
-Section: vcs
-Priority: optional
-Standards-Version: 3.9.8
-Build-Depends: debhelper (>= 9), libssl-dev | libssl1.0-dev, xsltproc, docbook-xml, docbook-xsl
-Vcs-Git: https://www.agwa.name/git/git-crypt.git -b debian
-Homepage: https://www.agwa.name/projects/git-crypt
-
-Package: git-crypt
-Architecture: any
-Depends: ${shlibs:Depends}, ${misc:Depends}, git (>= 1.7.2)
-Recommends: gnupg
-Enhances: git
-Description: Transparent file encryption in git
- git-crypt enables transparent encryption and decryption of files in a
- git repository.  Files which you choose to protect are encrypted when
- committed, and decrypted when checked out.  git-crypt lets you freely
- share a repository containing a mix of public and private content.
- git-crypt gracefully degrades, so developers without the secret key
- can still clone and commit to a repository with encrypted files.
- This lets you store your secret material (such as keys or passwords)
- in the same repository as your code, without requiring you to lock down
- your entire repository.

debian/copyright

@@ -1,64 +0,0 @@
-Format: http://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
-Upstream-Name: git-crypt
-Source: https://www.agwa.name/projects/git-crypt
-
-Files: *
-Copyright: Copyright 2012-2015 Andrew Ayer
-License: GPL-3+ with OpenSSL exception
-
-Files: fhstream.cpp fhstream.hpp parse_options.cpp parse_options.hpp
-Copyright: Copyright 2012, 2014, 2015 Andrew Ayer
-License: X11
-
-License: GPL-3+ with OpenSSL exception
- git-crypt is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
- .
- git-crypt is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- GNU General Public License for more details.
- .
- You should have received a copy of the GNU General Public License
- along with git-crypt.  If not, see <http://www.gnu.org/licenses/>.
- .
- On Debian systems, the full text of the GNU General Public
- License version 3 can be found in the file
- `/usr/share/common-licenses/GPL-3'.
- .
- Additional permission under GNU GPL version 3 section 7:
- .
- If you modify the Program, or any covered work, by linking or
- combining it with the OpenSSL project's OpenSSL library (or a
- modified version of that library), containing parts covered by the
- terms of the OpenSSL or SSLeay licenses, the licensors of the Program
- grant you additional permission to convey the resulting work.
- Corresponding Source for a non-source form of such a combination
- shall include the source code for the parts of OpenSSL used as well
- as that of the covered work.
-
-License: X11
- Permission is hereby granted, free of charge, to any person obtaining a
- copy of this software and associated documentation files (the "Software"),
- to deal in the Software without restriction, including without limitation
- the rights to use, copy, modify, merge, publish, distribute, sublicense,
- and/or sell copies of the Software, and to permit persons to whom the
- Software is furnished to do so, subject to the following conditions:
- .
- The above copyright notice and this permission notice shall be included
- in all copies or substantial portions of the Software.
- .
- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
- OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
- ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
- OTHER DEALINGS IN THE SOFTWARE.
- .
- Except as contained in this notice, the name(s) of the above copyright
- holders shall not be used in advertising or otherwise to promote the
- sale, use or other dealings in this Software without prior written
- authorization.

debian/gbp.conf

@@ -1,5 +0,0 @@
-[DEFAULT]
-pristine-tar = True
-pristine-tar-commit = True
-debian-branch = debian
-upstream-tag = %(version)s

debian/git-crypt.docs

@@ -1,8 +0,0 @@
-CONTRIBUTING.md
-NEWS
-NEWS.md
-README
-README.md
-RELEASE_NOTES-0.4.1.md
-RELEASE_NOTES-0.4.md
-THANKS.md

debian/rules

@@ -1,7 +0,0 @@
-#!/usr/bin/make -f
-
-export PREFIX=/usr
-export ENABLE_MAN=yes
-
-%:
-	dh  $@

debian/source/format

@@ -1 +0,0 @@
-3.0 (quilt)

debian/source/options

@@ -1 +0,0 @@
-single-debian-patch

debian/source/patch-header

@@ -1,17 +0,0 @@
-Subject: Collected Debian patches for git-crypt
-Author: Andrew Ayer <agwa@andrewayer.name>
-
-Since I am also upstream for this package, there will normally not be
-any patches to apply to the upstream source.  However, occasionally
-I'll pull up specific upstream commits prior to making an upstream
-release.  When this happens, this patch will collect all of those
-modifications.
-
-I use Git to maintain both the upstream source and the Debian
-packages, and generating individual patches rather than using git
-cherry-pick takes extra work for no gain.  Since I'm also upstream,
-there's no need to separate the patches for later upstream submission.
-Hence, I take this approach with a unified patch when it's necessary.
-
-For full commit history and separated commits, see the upstream Git
-repository.

debian/upstream/signing-key.asc

@@ -1,135 +0,0 @@
------BEGIN PGP PUBLIC KEY BLOCK-----
-
-mQINBFNTDEsBEACiZ+AWNaj80CvSIV9T+mlPClETM+pxEHuB+vldasG+BWsyyb2d
-AH390MSjXzs4RaiDGAXgZKnP9bhlWV/6BYcF0edz+G+Ux89L+D/c6miWFqwywQ7G
-FRBh10WDriNbSF6UoD6TJX9Kc2KIgeDQ7LFL1PsiFjsO/cUBfDmSvMWd/zzIV4Ug
-QdqFjjHdPSTr5w9D5YDS5FY2UOmcrxyNU66PoGkIp0Cqjgaieszxx3/CkGtktn0T
-M/dwP+yafgH5uUDRfgFR5McTvu4E53CAimsiv05wodXmnoELojVDrEYciJIrfGRx
-fCj+tiWsz0IcJCJ/ND1UExlI5so5tx0YaYMapx3PCb7+ZrZEUrRa3xK6m+ZU2Qfk
-XQJmUSnKuIsKP4Uo8ysMPxDuWrCap4nxw2uNsGgPXXnExJgVoWfyR0qMr16+BUSu
-Yrtfng19npv/Y381Y6hB8uRWRNRbaG8MEAHrgdPkb6853cbXT6A+k3KbZJVcEZsv
-XCS2lFuWaZTQGA1G4mj7TbudjvHLuDV8VbPsyxotgAHITSh6pekBuJFPOVhAZN41
-HyPNMZnE7eoW6DmShrdC+TjIVpzliqiLytDfGabIMNbnQDWdHxhzqq/Vn07ObOVp
-0MGn7PaGeyF+rmi0h1ttab3Dioku49dljjuz+uNhBcu1CB/CegIdtRVyDwARAQAB
-tCJBbmRyZXcgQXllciA8YWd3YUBhbmRyZXdheWVyLm5hbWU+iQI6BBMBCAAkAhsB
-BQsJCAcDBRUKCQgLBRYDAgEAAh4BAheABQJTUwz6AhkBAAoJEBA3jvwggAgM0BwQ
-AI8tAYxpeHyN+6StVAiu+wY2n2SNuunsORVmqyiICDOruxPTr4ulsP8vKM7Y4L9H
-lpJqfW/g65cByuZ48dFciQmI97RfZjjZgAxejM1dq/Y0RJGpZ6I7pNNbWIxvDm7o
-8mMeEQYT5S4vZKmreYZpzjLLZin+3gpBfljapGRikZNC1dzQu5JA0iCkWqIWmgto
-O/kEmGKID9ShLB0H/f26K+jKfKuQ2unqlPgUPlQfd65yBN0m0SaESozs5hnCjMxS
-oJSDnI0Kst0W/E/c0RZp5WJ3PECqnV0ru7xazMPLP3yNMrJVv3s6rKdiwzkQYUDj
-10KxCDOChc9UfVRZfiVc4OlnK77L5EM3AWLrNOwx8ntcs67hJXrppoDVin87PyMG
-SJE+DNKZk40oHLIrWCE43zS8p0k4OSGpJhiVev/o2FJImIiZXdYrm0gA3rA5OOM2
-nDSyPlB0kOzMN03z7pzT319OMhf5KZgYRuoAU59IqdW+Iz2q1vfusuh0UU5GfP+U
-XOuiiv9O9VqPTxpDOzmk5qnw8p3NNdwnqzop64wcBsNebyWGM52Hetd8bIwdFniI
-XsBhzRxnMVmNdXwQ7zhPKwpgGA9vWkyZ15EuhDK0Wc3XQf51NWVjY9Pt/NgpwKli
-CEqnd+sUszM78jXhvZjsWEkophudU6O615zYEEpTe+b/tB5BbmRyZXcgQXllciA8
-YW5kcmV3QGFnd2EubmFtZT6JAjcEEwEIACEFAlNTDM8CGwEFCwkIBwMFFQoJCAsF
-FgMCAQACHgECF4AACgkQEDeO/CCACAxWoA/+NYvxCoJ4V/TGZnYQJxT95qK+8uGS
-sQmlAYlIbYAAr0zxe1+U0HxMVMh0pj211B8Nd6Qq46X2ZYmWSyAPA6tiiSg+Y5C9
-2IGyCZ11oG98Op99nnPOEnKAPVgTtGgpMeomTPo768ucj0kvvbibGg3yMs1JBH2p
-wBULHZLCswlKzDOgg4YZfa5eicXRJOjl1EVbdhPyMZrnJB5bFnkno8rSIJ1h3QkV
-kWAJ0bPggHxsWiYOEJUjEkzr4zXjcCJKIyPWY9rZcgJNvo1Bwqx/E7Cs+XABuPtU
-0OPIysXROANzsUMVt0NpcSJsAPJxt5L5EoCVRhTDjaK6kXglEcxqOqSzTsu61cKj
-MAAyZY+qfTA2ILzPYgxiy+h4ReUxAHx0Bzd7w6L+tn1aPlc9nqDm1nzk9U8rzA5j
-XDJJJOuC5yCzhQ2tpsAp/RRE+1sgiGV8D+LSXf2ZYBQbV9V6icFdhHUrqKzQsw7m
-5C4n2Fk1wk54JTFO1j4rWarHiVeKuKWiBrQhhUJqFtJ/lpr6tIVsI5KuoWczHpQ0
-RhCnUNFPj1JaMM09pLEkg9u/RRrVo6eSHy0vHKCqYZYUAldTGpE18kRlpTDgrN8T
-jhBaiFrk8PBKPiE4Pt+5BgDZr8jP+CWA9Bc06E6EtV+fDdTexAj2Uw0JE0zZdhQc
-1J1NNIMHc4WpS6+0JEFuZHJldyBBeWVyIDxhbmRyZXdAYW5kcmV3YXllci5uYW1l
-PokCNwQTAQgAIQUCU1MMjQIbAQULCQgHAwUVCgkICwUWAwIBAAIeAQIXgAAKCRAQ
-N478IIAIDDg1EACQ+stApB16L54LnS7YMFUHeUgaG3Hfu+WmIrvRn5UcT4hxRNsY
-/c7nDumrwAmg8HiOXwe7V8MJMFUEEoQylWpYLFzOTlwDmVGUMczQScgi7RvK9zwJ
-0475Wlpr/7wUrG0LyinLVf7GoKPtIkefzlydTzMu4xSr52t1sSGQqcWXDVJ2bCGf
-KuvmDpv1gOORdp4g2lI0wOPWgPzm4ctqhzT58jFR5vQpzpr+H0qB35prcKa9TAIG
-sbtF1bdSaOBkXev/IFhY07Fq35aqEuv27+aMJkYjhzIVSnm+/9Io/1L0RTpHZpgc
-px08yfllq7Vf0buCiC8uEvdFVL4sHOlp9gVU21boLj4JJnZvlJ1m+gfIMAfhtt4R
-2QNxKxC+jO2bBvj4j9dHBz0MQvAoJl121cjOAxZGMHye3eV0sHtE7UntxA5pQQv0
-U2hx7A70yAlN2Np76xVDO9cae4aVUV7lCdY14L9e5Ww4mAknFMeIgbkoxWT2lMA+
-1pfn541c6XUuuNfr1D9flYHbDFEYTUOFZ6ypAgOxkK+/wPYlz4d6MTBJ4fcoEhSF
-qX0JVFW8Jrnqs4GsDmej9dibfYdk2a0qG69oSRF8Bujxdh41R+/C03LSnRBXhjHJ
-SG/xSYoCcOL6y3aiJb2gK2lbrLxmeysCn7goGPp16VikSxHNFJkigRUqDbQhQW5k
-cmV3IEF5ZXIgPGFnd2FAYW5kcmV3YXllci5jb20+iQI3BBMBCAAhBQJTUwyrAhsB
-BQsJCAcDBRUKCQgLBRYDAgEAAh4BAheAAAoJEBA3jvwggAgMfWsP/2F+Ds4lIn7p
-rdgEeK2kT4Sxn4ldATU8ZKjVe/RnTxWx+jqEHdsXkUAVEHNuUPYwtvETub2mMFBr
-lguL1WWW09J1ihYEk4ErDT81kNP+8cGGDjLkv8FWjlLPUGrcZRMj52JP0saW7AIJ
-2/OxvpC00xkpb5goy5yXUKVgzBhVUAcSx1a3vY92y+RnmcwhnQmlhAy+xpyO0Ju+
-dEhNfBny+gc/YdWfha6sWed6fL0VWut2l1euEU9WIH/Mcd8NWGs10ez9iqVhRWi3
-zpTWxkVBY0+PaPaHkqh6N3cCDEdFXXmVtP3nPvC+4k6vIUK+frIIffjDlOXhXaPB
-bGZ2SyJcYJdsh6Lb3cnQ2ISHrlKy2CgVkExdgz8JeSF296OInQJmS/U9XFH2iN/w
-Yivi93pUV9xvPaJTXOSUMA+szKXapPTH8zUNQ99tm7KiwV0aMXWKG0iNxjg7C0kO
-vVuKGBKEpFdyNLL7uAE/bzs7WVZ8ztebZJTlScIU7KZUr931kR++VAzIFr7yYlaC
-4c2TjiinStFsHgfRqaVoJfQIWQzxrli46LkaIVur3rzBJERNSpDcPlpF1wngXkFo
-Jqt+c7MTVBeoaaAv5TAK0a/D027fUNtAyxtCPmkoHs6BWh38NDGO7VNBRNog0Vnm
-ItcFmFtM0rcQV6DbUjUZdTYygPGq0MAWtCNBbmRyZXcgQXllciA8YW5kcmV3QGFu
-ZHJld2F5ZXIuY29tPokCNwQTAQgAIQUCU1MMwgIbAQULCQgHAwUVCgkICwUWAwIB
-AAIeAQIXgAAKCRAQN478IIAIDDN4D/0eINLgeE2mHs68kM6fXRf0jfDdyVYMvxnK
-ZO0jq1sjurEYgw+tHQRHo5bsu52E1yneoam5pzucu6TXUVc2X7dGKfuqvsU55+Qo
-IlqE0ai0tXlmc7orVzZFgLCTGrZgL2NL208h3EvlSeqy//6yA/rirMIRiD/vSb3A
-u0EBXSav+x/o092W904jPzeLGGL9c9G6HxmAzGxRO0q5FfB7u1sI9bpgljC3mBVb
-jUhD/ynIwkIZfTgQFRlBHtzy0HpcnlzxzcY7b/SB+8was1aEDetzuEeXOdTDXxd6
-gVBFDZMyKtZU5jsprZDU6/nleka6/ji6ZMNIJvMgcJbgwV3i/ipKH3FfItcnTt+F
-gx2q3j/pVYPyKo05tp2dBCgdyEKsTgc+QTqo0EOk5to8Gz7ebkyPGIELqIfBtPjp
-hoB9oTpgmnAsgSnSGDfz4yD+8uU3FBOjrMNe5tucq+N8VVYZhCQFs8fAbrghh568
-ahBcLDu4n9OvjZz5hHnpARtSOw2WmLdQ43JAnFa6F8rN98ymlP6X8CT3lTnPwkRL
-+9l008KXP64nZStISozKwDb4zMfRn7iHbqs6reIlvgIOevkiMmPTyhhQ0zz6aLwy
-ZNcQPK7wdXtynPydzAPfKbxfQkVpkQb/mgBgr2blZSu4Z5W491tDOTI/MF0gMTfA
-eqavC9PhRrkCDQRTUw1OARAAyr3w+DujjQ+oiLrlnGu+DArnxK5lf8DzeVokFlSX
-TJXSgCl4niJeQhodn3EtnDRdKimdvMxgW+iVU4MKhK/2xbf0rNSQDJv4iIub0wHH
-Y8kkqsBU3vDjoTYraoFMjKWIvZEr9FJTiDgX4VruJAhwydjknrSWdK7As9PzqU0l
-C7ReHRJIJLu20EeVCVoGuyVmRfendTXDbflvZhUhTitcgJbNek272u521lYbk3g1
-knMWhwmdsy95ZqNbjk4iMJ6eq4l2MA/yka4V4zA7P9L0WBjuFyImVix4WyaF+TIN
-/t8eX+zF6VfImoKlMer8qpMmGaFBKxOdGdAH+YpoP8sysSrFDV0iSbA/WwbNa4e7
-F8eras4B/sFWIldXlSd0yLqdNe8ZB0vPDS44tNcmDYz3cWIH1mDF1AbHDBbOxwa+
-FkcHDPjYrnIQbFI3Z+rzOqc8vOeiNPHggPSDRjM6duah4aOLp6RYEYc/2ouO1yMD
-UlWQ+eGDvqAvIt3HH2y78fbkl3K2VVA+gd5w9oxDKxXKZxp/y5RVVYCZUAv1lllT
-87dRMXignTVEIsF8VdESrHhRYUQW+2wP40hKZIPEaWS5BSH/d/qGgDSBsVPbDlas
-4n3FJ+SVil6xm0hJ+29Xw/GDMc+uQfs8TkPxbM0cjn59oZb6I3Zhxy+KWSxdCN2g
-8nMAEQEAAYkERAQYAQgADwIbAgUCU1MO8wUJB4TPXQIpwV0gBBkBCAAGBQJTUw1O
-AAoJEJ0V9ORH5MgyJTQP/0cSeXYZ+G7EKEjM+xHfjUyNavahVZ+rfiLzZpU+os4s
-SGwd4annJ4Z56UMA+1U5Qm34+rH+E72qTJAEhg512CQJnFejVKqBuVzBsxaO5aLK
-nSafGk3Ixev4JraspFtDmSflVHrQFVKeu3oF+tjE2elHHhhV8I1N8eA2HTiwlTpD
-9RgQ1nFw9KM4+ncBm56dK3lVQbgT7XPz6noIPhXpAKH1THthvIyjUDyTqeRUrgHL
-eeFtKXWnsiUMi5z3dz1lK0QacGaykl+VtLXlUIffh7IpLp3MoiaboXV2UdocIrZ3
-vg00wBrZ01w7L10LB0Jl1NEH5ccbezAVCaW3/2MT6C7BnQZqpjQiKncrnx2YoupJ
-+OWJT2QOQoLOKwL4ShHB8Dae4RD0aTcmTTVBEteSvH32hhcsXChMi1Dzsf6cvNmV
-pl54VkfWmZqyfTl7LjqpQsOcUtDshFPQMziKF8pSyhSYiuImvLFwypTe4KtDqA/U
-d1v9XB40mniAUTC5dWO+80MhOB4NpXNNSXP22DzpDZvfhdTxSCwc70bpWJIRVpuT
-gVvVjqOiCVanNXqwh14Nn+/SaRDx19BglXhniBWNEXN8f2dhI3YkZ2ovS/t6mfxn
-aymghsKL1yvu8zdTFZsmAhYdpTBIB9zMjoNs3TNb8I+X26oPUjSKZ1/+oAacGTtJ
-CRAQN478IIAIDBXvD/sG09+tMC30Tcq6DuycebKiuHfIioBdWTNLTz3Pahi0C/4e
-WDcd0H8hcxUz9cdBnUs5uvUwdo07bqVb+zJ0PidDdCpCSDwNH9Zn98Duy7QVPtAU
-psPApSe2Y23zh4tr37c31dlUIsRCiGfjIjjoCFg3NZMxmw4y3UhUMPNemDt+rB+t
-XmstUc03xdaUrrssAxZf/qhNy9tPucHGl1Uuq1c8ANhdgmosMacfxb9i/kcCErTl
-Kz3DwZPVdE4Q/KcaiTOBxBthlvpZM27h//BeT/Yo2Hy/X7nzhhyscPqaDj/HOCbt
-O/wyH/kv4z++bzy7FSERMJTQvAaYEbhWE71l+sSBJT1ZJnafDXX+b9ZlSE7Im5C8
-mjGc1XX9Mw1eXzLh7wiC+BEEr4S9qOkyKtSKcQ/m+UjOARXrqA1qhDp1mmhSVNsW
-UnhWabsO9TwxcRdSX98ql+rNYBjN7tsqzq3G3R3oFeaGevAqPqJFbAFhGhB33UP1
-yolOPxGP6u2NdNFmGQ2vVlzJNzY5QAk2cekIZWJLd8YEcXeijPo1BX4eTg4V6d61
-EWIKoSHBeKVwhuCg9l6ZFrNzUoHGP4yKDXJood71KBulDSSUkzIM05ngfcajz1RS
-R9szqJlNAuLHpQHOZEI1k38sQrnPoqwzyshgU7S/vLAT6hr666bJ2i9l82X077kC
-DQRTUw4RARAA30ouhOBeAX4ORzDmeyP9MjuDZWArkJv22PI5ijISIyRjUdYogvqY
-XAm2z0RTzD4waW9lSabumDqVGd5MzTm0GTaIw/E+7rx08vnBVRlHLpAOZMUogNEG
-p+3uXhgHmar0uhVhYar1v6SUqscray+wtnkRnXQkitkD0zzTWGx17LnWPOguNDsU
-uYjWoAYgEiS9g3UYLfexQRVxae7n6YTDedNfjuMKAmmc+ixWDHQ9Dcjc4oJacV5z
-iz78NYdXoPA3101lKPzUGqRye/Rvm0/GXzht5nhsIMB/X/FIk6qlbCAP/VpVRpYD
-KE7N3juJY7jwoCze9d3TZx6jU8IR/rD1uuDW/gjyPVAHAcE1fRwjErtR1TsFcXdY
-wtTJx+Rzq6gaS1mfeV90/V2RY0i+nqGhmY+o+lLt1uozX3iTO2X9cF/REp9i6Rly
-TOUMAPW7mOryN9Yv/WAkG4S/WgtnZRCA0M88jFSgX8go+Y2Z6yAUynEXDREH9VMI
-rw0kNhvOzfWSAyBOuNfNrehShR6RMtAKs/JC+VEwhvDD+avFNHywpn7fGMa2WqFw
-x337Yz6wARJ5g9vBCMJBWMhWT62cMQK62TLVkW5lbULSVwUAsbNyZMaQks7kfas3
-9w3gr66Bc/2v4PaQMUQ3I79yO/f6zsxu9vZ1yxPtKOGwGHQvnCdRMlMAEQEAAYkC
-JQQYAQgADwIbDAUCU1MPDQUJB4TO+QAKCRAQN478IIAIDFQcEACFi6e4/++dhkPT
-e1dnaifmSINXthSFkOAp8OR0mK2/0Ged6UmbyxPd7gKQJUXFV5Mz5Sj8G6N4YCLl
-+55k67gwZwzZ62EYB41FnjkXKILBgP+mt2c0SCuwwwz9g8Jx351l2Cfatz6SoviE
-XjQURDHPxsqK1mfKMmoMWo4Ii68hzKrBg0mcdxeJeYj/t8l0ug2JQApnJsaE+5QC
-3U9txBYm1Rpsaz/IFvlGJS9CkZyQA7ci/eMmoKn+/R8Gk48avkM0vFmUz9T8saIr
-g0F5T7ThjC8575PNtInpDZRp9V3PdeKtiA9Fky11fNi0VS7luurKQ3I0UJfdyxe1
-Sb/kvwSu++zEDEG5/li4GfMBqiZTV6oZJ9fzZnrGjEyiRSLN7GA4T1KC795zm/63
-MrTaTf/3G6iRLNcvEdcWTiSHlFSkpx+qQHoijs0KU6uzdvHwtKKX/UBrk837SOFL
-AEqn8ebsOKYiO4gA0ismpAt9NQwqsKq0rhyZAIDl9hSjwGBqX24NA7qnkoZNZySC
-YBn0ZZRr3VGyeNWgtZg/KIiyKX7xmEUgBswt/U42x5wG3SdhAiSn6If/y8dTpfzT
-kXF2+jp/tbGpm1qHi6qrkdMqCHCf67beh9SmlKa8nYyb1fpEcNBBElA8AAFgaYKh
-zZq3C24mS3JwlqDwjT/Ut1/tChr3wQ==
-=ZMwd
------END PGP PUBLIC KEY BLOCK-----

debian/watch

@@ -1,2 +0,0 @@
-version=3
-opts=pgpsigurlmangle=s/$/.asc/ https://www.agwa.name/projects/git-crypt/ .*/git-crypt-(\d.*)\.(?:zip|tgz|tbz|txz|(?:tar\.(?:gz|bz2|xz)))

key.cpp

@@ -232,6 +232,11 @@ void		Key_file::load_header (std::istream& in)
 				key_name.clear();
 				throw Malformed();
 			}
+		} else if (field_id == HEADER_FIELD_SKIP_EMPTY) {
+			if (field_len != 0) {
+				throw Malformed();
+			}
+			skip_empty = true;
 		} else if (field_id & 1) { // unknown critical field
 			throw Incompatible();
 		} else {
@@ -256,6 +261,10 @@ void		Key_file::store (std::ostream& out) const
 		write_be32(out, key_name.size());
 		out.write(key_name.data(), key_name.size());
 	}
+	if (skip_empty) {
+		write_be32(out, HEADER_FIELD_SKIP_EMPTY);
+		write_be32(out, 0);
+	}
 	write_be32(out, HEADER_FIELD_END);
 	for (Map::const_iterator it(entries.begin()); it != entries.end(); ++it) {
 		it->second.store(out);

key.hpp

@@ -83,18 +83,23 @@ public:
 
 	void				set_key_name (const char* k) { key_name = k ? k : ""; }
 	const char*			get_key_name () const { return key_name.empty() ? 0 : key_name.c_str(); }
+
+	void				set_skip_empty (bool v) { skip_empty = v; }
+	bool				get_skip_empty () const { return skip_empty; }
 private:
 	typedef std::map<uint32_t, Entry, std::greater<uint32_t> > Map;
 	enum { FORMAT_VERSION = 2 };
 
 	Map				entries;
 	std::string			key_name;
+	bool				skip_empty = false;
 
 	void				load_header (std::istream&);
 
 	enum {
 		HEADER_FIELD_END	= 0,
-		HEADER_FIELD_KEY_NAME	= 1
+		HEADER_FIELD_KEY_NAME	= 1,
+		HEADER_FIELD_SKIP_EMPTY	= 3	// If this field is present, empty files are left unencrypted (see issue #53)
 	};
 	enum {
 		KEY_FIELD_END		= 0,

parse_options.cpp

@@ -43,7 +43,7 @@ int parse_options (const Options_list& options, int argc, const char** argv)
 {
 	int	argi = 0;
 
-	while (argi < argc && argv[argi][0] == '-') {
+	while (argi < argc && argv[argi][0] == '-' && argv[argi][1] != '\0') {
 		if (std::strcmp(argv[argi], "--") == 0) {
 			++argi;
 			break;